• WordNet 3.6
    • n clearance permission to proceed "the plane was given clearance to land"
    • n clearance the distance by which one thing clears another; the space between them
    • n clearance vertical space available to allow easy passage under something
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Webster's Revised Unabridged Dictionary
    • Clearance A certificate that a ship or vessel has been cleared at the customhouse; permission to sail. "Every ship was subject to seizure for want of stamped clearances ."
    • Clearance Clear or net profit.
    • Clearance The act of clearing; as, to make a thorough clearance .
    • Clearance (Mach) The distance by which one object clears another, as the distance between the piston and cylinder head at the end of a stroke in a steam engine, or the least distance between the point of a cogwheel tooth and the bottom of a space between teeth of a wheel with which it engages.
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Century Dictionary and Cyclopedia
    • n clearance The act of clearing; riddance; removal of encumbrance or obstruction: as, the clearance of land from trees; the clearance of an estate from unprofitable tenantry.
    • n clearance Clear or net profit.
    • n clearance A certificate that a vessel has complied with the law and is authorized to leave port. It contains the name of the master, of the vessel, and of the port to which it is going, a description of the cargo, and other particulars. The manner in which a clearance shall be made is prescribed by law.
    • n clearance In steam-engines, the distance between the piston and the cylinder-cover, when the former is at the end of its stroke; similarly, free play for the parts of any other machine; clearing.
    • n clearance A piece of land which has been cleared for cultivation or for building; a clearing.
    • n clearance In railroading: A difference between the track-gage and the gage of the exterior surface of the wheel-flanges, designed to allow a certain amount of play between the flanges and the rails.
    • n clearance At a crossing or frog, the clear space left between cross-rails and the frog and guard-rail for the free passage of the flanges of the wheels.
    • n clearance The clear space between the sides and top of a tunnel or bridge and the outside dimensions of the largest car passing through it.
    • n clearance In steam-engines, the volume or entire space below the valve-face which is filled with steam at the beginning of a stroke, including the space between piston and cylinder-head and the volume of the steam-ducts to the valve-seat.
    • n clearance The settlement or payment of a debt; the passing of checks and drafts through the clearing-house for their settlement.
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Chambers's Twentieth Century Dictionary
    • Clearance act of clearing: removal of hinderances: a certificate that a ship has been cleared at the custom-house—that is, has satisfied all demands and procured permission to sail
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Chambers's Twentieth Century Dictionary
Fr. clair—L. clarus, clear.


In literature:

Owing to the clearance of the fire trenches, the assaulting parties had, unfortunately, to move across the open.
"With Manchesters in the East" by Gerald B. Hurst
A report was made that Rotch had been refused a clearance from the collector.
"The Great Events by Famous Historians, v. 13" by Various
That I, myself, have top-security clearance for my special projects?
"Occasion for Disaster" by Gordon Randall Garrett
Where are my clearance papers?
"Fire Mountain" by Norman Springer
And Professors who drone while their pupils are sleeping, Though they went at a loss, we should welcome the clearance.
"Punch, or the London Charivari, Vol. 98, 1890.05.10" by Various
The Old Man would give them a pre-paid vacation clearance to any resort in the world or out.
"The Real Hard Sell" by William W Stuart
I'll give you a city-wide clearance as an executive.
"The Cartels Jungle" by Irving E. Cox, Jr.
How could you get over the fact of having no clearance papers, and all the rest of it?
"The Recipe for Diamonds" by Charles John Cutcliffe Wright Hyne
Entrance fees had to be paid, and clearance papers must be got at the custom house.
"Hero Stories from American History" by Albert F. Blaisdell
Entries and Clearances together, in Millions of Tons.
"Are we Ruined by the Germans?" by Harold Cox

In poetry:

DAPH, SPAR, NICE. Great Jove, this interference.
Is more than we can stand;
Of them make a clearance,
With your majestic hand.
"Thespis: Act II" by William Schwenck Gilbert
Those that with gospel-clearance meet,
Must by the law be found complete;
Yet never could (again I grant)
The gospel justifies a saint.
"The Believer's Principles : Chap. II." by Ralph Erskine
An' made straight for the dairy door.
Thar's times in most experrence,
We feel how trooly wise 'twould be
To make a rapid clearance;
Nor wait tew practice them thar rules
We larn tew city dancin' skules.
"Old Spense" by Isabella Valancy Crawford
"That Anzac have a name?" I asked, the old bloke didn't know.
He said, "Those who could have told me passed on long ago."
Anyway the old bloke kept on talking, and according to his tale,
the photo was unwanted junk, bought at a clearance sale.
"The Anzac on the Wall" by Anonymous Oceania

In news:

Author's clearance suspended pending outcome of investigation.
Broadwell would have classified clearance .
The woman at the center of the scandal that took down CIA Director David Petraeus is without her military security clearances right now.
Cutler still awaiting clearance to play.
EU Merger Control Clearance .
Smith can't get medical clearance .
Alex Smith will miss his first start since 2010 tonight after he was unable to get medical clearance from a "neurologist" one week after sustaining a concussion, ESPN's Chris Mortensen reported.
UCLA's Shabazz Muhammad gets NCAA clearance to play.
Isle of Wight to pursue pre- clearance waiver.
New York & Company: Storewide 50% off everything (excluding clearance ).
Christie Dedman cdedman@al.comNew York & Company has marked everything in the store excluding clearance and new arrivals 50% off.
Broadwell Loses Her Security Clearance .
Official: Broadwell's security clearance suspended.
Paula Broadwell's security clearance suspended.
Army suspends security clearance of woman involved in affair with Petraeus.

In science:

Under full state feedback, the agent controlling the clearances can fully observe state of the surface state.
Environmental benefits of enhanced surveillance technology on airport departure operations
If the number of aircraft is greater than the threshold, no pushback clearance is issued, and k = 0.
Environmental benefits of enhanced surveillance technology on airport departure operations
The quantum noise at this stage has an unbiased Gaussian distribution with a normalized mean at 0 dB and dark noise clearance of 8.5 dB. (d) High randomness of the final digital random numbers depicted by the featureless color plot.
Real time demonstration of high bitrate quantum random number generation with coherent laser light
Indeed, this issue has been tackled by many grid infrastructures, either by providing access only to a fixed restricted set of software applications, or by requiring clearance procedures to elevate a subset of the users (“ VO operators”) to the privilege level needed to install software on the execution nodes.
Batch-oriented software appliances
The cryostat will incorporate two or more support mounts that will fit in the clearance between the EMCal and the outer skin of the cryostat.
sPHENIX: An Upgrade Concept from the PHENIX Collaboration